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Journal of Hydrodynamics 2004年第6期16卷 737-742页

作者： FANJing-yu wangdao-zeng ZHANGYan ShanghaiInstituteofAppliedMechematicsandMechanics ShanghaiUniversityShanghai200072China

The three-dimensional mean and turbulence characteristics of an impingingdensity jet in a confined cross-flow were numerically investigated using the RNG turbulence *** comparison of the subregion structures and gross features between the numerical results and theexperimental data show good agreement. The velocity, Turbulent Kinetic Energy (TKE) andconcentration distributions of the impinging jet in near field were obtained and analyzed. Theresults indicate that the flow and concentration fields of the impinging jet in the crossflowexhibit distinguished three-dimensionality in the near field. There exist upstream wail vortices anddownstream wall jet zones in the impinging region, and the TKE and concentration decays areasymmetrical in relation to the stagnation point. The lateral concentration distribution range inthe impinging region spreads considerably. The enhanced entrainment and mixing of the impinging jetin the confined crossflow are mostly associated with the impinging action and lateral expansion inthe impinging region. The presence of the bottom wall restrains the formation of the span-wiserollers in the transverse jet region and vertical entrainment and mixing in the impinging region andthe transition re-gioa

关键词： impinging jet crossflow entrainment mixing

INVERSE PROBLEM METHOD FOR WATER ENVIRONMENT TOTAL CAPACITY CONTROL OF A TIDAL RIVER

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Journal of Hydrodynamics 2005年第3期17卷 323-329页

作者： wangdao-zeng ZHAOYu-feng LINWei-qing ShanghaiInstituteofAppliedMathematicsandMechanics ShanghaiUniversityShanghai200072China ShanghaiAcademeofEnvironmentalScience Shanghai200233China

In this paper, an improved method for water environment total capacity control of tidal rivers was presented. The maximal capacity of point pollution sources for the Huangpu River was computed by this method, and the result was compared with the practically observed data. The numerical result shows that the method is effective and efficient.

关键词： inverse problem tidal river PST-BFGS method point source pollution Huangpu River

WAVES GENERATED BY A SUBMERGED BODY MOVING IN STRATIFIED FLUIDS AND VERTICAL STRUCTURES OF INTERNAL WAVES

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Journal of Hydrodynamics 2004年第1期16卷 113-114页

作者： WEIGang DaiShi-qiang MiaoGuo-ping HuangSi-xun TaoMing-de LiBai-qi LiuYu-lu wangdao-zeng YouYun-xiang ShanghaiInstituteofAppliedMathematicsandMechanics ShanghaiUniversityShanghai200072China ShanghaiUniversity ShanghaiJiaotongUniversity Chairman P.L.A.UniversityofScienceandTechnology FudanUniversity ChinaShipScientificResearchCenter ShanghaiJiaotongUniversity

This dissertation deals with the internal waves generated by a submergedmoving body in stratified fluids by combining theoretical and experimental methods. Our purpose isto provide some scientific evidences for non-acoustic detection of underwater moving bodies based onthe principles of dynamics of the internal waves. An approach to velocity potentials obtained bysuperposing Green''s functions of sources and sinks was proposed for Kelvin waves at the free surfaceor interface in a two-layer fluid. The effects of interacting surface- and internal-wave modesinduced by a dipole on the surface divergence field were investigated. A new theoretical modelformulating the interaction of a two-dimensional submerged moving body with the conjugate flow in athree-layer fluid was established. An exact solution satisfying the two-dimensional Benjamin-Onoequation was obtained and the vertically propagating properties of the weakly nonlinear long waveswere studied by means of the ray theory and WKB method. The above theoretical results arequalitatively consistent with those obtained in the experiments conducted by the author.

关键词： stratified fluid internal wave kelvin wave flat solitary wave algebraicsolitary wave conjugate flow green''s function benjamin-ono equation

Comparative Study on Different Methods for Prediction of Thermal Insulation Performance of Thermal Barrier Coating Used on Turbine Blades

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Journal of Thermal Science 2024年第1期33卷 172-189页

作者： ZHANG Zhixin zeng Wu ZHANG Xiaodong zeng Yuntao Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As turbine inlet temperature gets higher and higher,thermal barrier coating(TBC) is more and more widely used in turbine *** turbine blades with TBC,it is of great significance to evaluate the temperature distribution of its substrate metal quickly and accurately,especially during the design *** different degrees of simplification such as whether to consider the change of the geometric size of the fluid domain by TBC and whether to consider the planar heat conduction in TBC,three different methods used in conjugate heat transfer(CHT) simulation to model the TBC of the turbine blades have been developed and widely used by ***,little research has been conducted to investigate the influence of the three methods on the temperature distribution of turbine *** fill this gap,three geometric models were *** are a solid conduction model with a substrate metal layer and a TBC layer,a transonic turbine vane with internal cooling and TBC,and a plate cylindrical film hole cooling model with *** methods were used in these geometric models and their differences were carefully analyzed and *** result shows that for the conduction model used in this paper,with the same TBC surface temperature distribution,the difference between the three methods is very small and can be *** a transonic turbine vane with internal cooling,regarding the local maximum temperature of the substrate-TBC interface,the largest difference between the method in which TBC is considered as a thermal resistance or a virtual layer of cells and the method in which three-dimensional heat conduction equation of TBC is solved occurs at the trailing *** difference near the leading edge is below *** employed to the film cooling model,the difference of the laterally averaged temperature of the substrate-TBC interface can be 8 K which is mainly due to the change of the length to diameter ratio of the film cooling hole by *** the substrate

关键词： turbine blade thermal barrier coating conjugate heat transfer film cooling hole

Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1163-1174页

作者： Meng Li Zhigang zeng Wuhan National Laboratory for Optoelectronics Wuhan 430074 School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method.

关键词： method saturation differentiable

Aggregation-regulated bioreduction process of graphene oxide by Shewanella bacteria

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Chinese Journal of Chemical Engineering 2024年第5期69卷 56-62页

作者： Kaixin Han Yibo zeng Yinghua Lu Ping zeng Liang Shen Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Chinese Research Academy of Environmental Sciences Beijing 100012China

The bioreduction of graphene oxide(GO)using environmentally functional bacteria such as Shewanella represents a green approach to produce reduced graphene oxide(rGO).This process differs from the chemical reduction that involves instantaneous molecular *** bioreduction,the contact of bacterial cells and GO is considered the rate-limiting *** reveal how the bacteria-GO integration regulates rGO production,the comparative experiments of GO and three Shewanella strains were carried ***-transform infrared spectroscopy,X-ray photoelectron spectroscopy,Raman spectroscopy,and atomic force microscopy were used to characterize the reduction degree and the aggregation *** results showed that a spontaneous aggregation of GO and Shewanella into the condensed entity occurred within 36 h.A positive linear correlation was established,linking three indexes of the aggregation potential,the bacterial reduction ability,and the reduction degree(ID/IG)comprehensively.

关键词： Graphene oxide Reduced graphene oxide Bioreduction Aggregation Shewanella

Eigenvalues for the Clamped Plate Problem of L_(ν)^(2) Operator on Complete Riemannian Manifolds

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2223-2243页

作者： Ling Zhong zeng Jiangxi Provincial Center for Applied Mathematics&School of Mathematics and Statistics Jiangxi Normal UniversityNanchang 330022P.R.China

L_(ν) operator is an important extrinsic differential operator of divergence type and has profound geometric *** this paper,we consider the clamped plate problem of L_(ν)^(2)operator on a bounded domain of the complete Riemannian manifolds.A general formula of eigenvalues of L_(ν)^(2) operator is *** this general formula,we obtain some estimates for the eigenvalues with higher order on the complete Riemannian *** several fascinating applications,we discuss this eigenvalue problem on the complete translating solitons,minimal submanifolds on the Euclidean space,submanifolds on the unit sphere and projective *** particular,we get a universal inequality with respect to the L_(II) operator on the translating ***,it is very difficult to get universal inequalities for weighted Laplacian and even Laplacian on the complete Riemannian ***,this work can be viewed as a new contribution to universal estimate.

关键词： Mean curvature flows L_(ν)^(2)operator clamped plate problem eigenvalues Riemannian manifolds translating solitons

Systems Theory-Driven Framework for AI Integration into the Holistic Material Basis Research of Traditional Chinese Medicine

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Engineering 2024年第9期40卷 28-50页

作者： Jingqi zeng Xiaobin Jia School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjing 211198China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

This paper introduces a systems theory-driven framework to integration artificial intelligence(AI)into traditional Chinese medicine(TCM)research,enhancing the understanding of TCM’s holistic material basis while adhering to evidence-based *** the System Function Decoding Model(SFDM),the research progresses through define,quantify,infer,and validate phases to systematically explore TCM’s material *** employs a dual analytical approach that combines top-down,systems theory-guided perspectives with bottom-up,elements-structure-function methodologies,provides comprehensive insights into TCM’s holistic material ***,the research examines AI’s role in quantitative assessment and predictive analysis of TCM’s material components,proposing two specific AIdriven technical *** interdisciplinary effort underscores AI’s potential to enhance our understanding of TCM’s holistic material basis and establishes a foundation for future research at the intersection of traditional wisdom and modern technology.

关键词： Artificial intelligence Systems theory Traditional Chinese medicine Material basis Bottom-up

Electrochemical conversion of organic compounds and inorganic small molecules

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Science China Chemistry 2024年第10期67卷 3223-3246页

作者： Weimei zeng Youai Qiu Department of Chemistry Nankai UniversityTianjin 300071China

Electrochemical synthesis presents a facile and sustainable strategy to produce valuable *** review summarizes the most recent advances in electrosynthesizing value-added compounds with inorganic small ***“small molecules”refers to a broad spectrum of chemicals,we mainly focus on the electrochemical conversion of CO_(2),H_(2)O/D_(2)O,NH_(3)and SO_(2)until March *** review intends to compare the results and display general trends throughout the field,with an emphasis on the substrate scope and mechanical ***,we propose several techniques and protocols that can enable a more fundamental understanding of the electrochemical reaction involving inorganic small molecules and help drive this methodology toward commercialization.

关键词： electrochemical synthesis inorganic small molecule organic synthesis carbon dioxide water

Analysis of gravity wave activity during stratospheric sudden warmings in the northern hemisphere

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Earth and Planetary Physics 2024年第2期8卷 415-422页

作者： XuanYun zeng Guang Zhong School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410000China Key Laboratory of Geospace Environment Chinese Academy of SciencesUniversity of Science&Technology of ChinaHefei 230026China

Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The variation characteristics of GWs during SSWs have always been an important *** temperature data from January to March in 2014−2016,provided by the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC)mission,we have analyzed global GW activity at 15−40 km in the Northern Hemisphere during SSW *** the SSWs that we studied,the stratospheric temperature rose in one or two longitudinal regions in the Northern Hemisphere;the areas affected extended to the east of 90°*** these SSWs,the potential energy density(E_(p)of GWs expanded and covered a larger range of longitude and altitude,exhibiting an eastward and downward *** E_(p)usually increased,while partially filtered by the eastward zonal *** zonal winds weakened or turned westward,E_(p)began to *** SSWs,the E_(p)usually *** observations can serve as a reference for analyzing the interaction mechanism between SSWs and GWs in future work.

关键词： stratospheric sudden warming gravity wave wind filter